SILC_TASK_CALLBACK(silc_client_protocol_connection_auth);
SILC_TASK_CALLBACK(silc_client_protocol_key_exchange);
+SILC_TASK_CALLBACK(silc_client_protocol_rekey);
extern char *silc_version_string;
/* Send the packet immediately */
silc_client_packet_send(client, ske->sock, type, NULL, 0, NULL, NULL,
packet->data, packet->len, TRUE);
-
}
/* Callback that is called when we have received KE2 payload from
SilcCipher cipher,
SilcPKCS pkcs,
SilcHash hash,
- SilcHmac hmac)
+ SilcHmac hmac,
+ SilcSKEDiffieHellmanGroup group)
{
SilcClientConnection conn = (SilcClientConnection)sock->user_data;
ske->ke2_payload->pk_len);
#endif
+ conn->rekey = silc_calloc(1, sizeof(*conn->rekey));
+ conn->rekey->send_enc_key =
+ silc_calloc(keymat->enc_key_len / 8,
+ sizeof(*conn->rekey->send_enc_key));
+ memcpy(conn->rekey->send_enc_key,
+ keymat->send_enc_key, keymat->enc_key_len / 8);
+ conn->rekey->enc_key_len = keymat->enc_key_len / 8;
+
+ if (ske->start_payload->flags & SILC_SKE_SP_FLAG_PFS)
+ conn->rekey->pfs = TRUE;
+ conn->rekey->ske_group = silc_ske_group_get_number(group);
+
/* Save HMAC key to be used in the communication. */
silc_hmac_alloc(hmac->hmac->name, NULL, &conn->hmac);
silc_hmac_set_key(conn->hmac, keymat->hmac_key, keymat->hmac_key_len);
}
}
+/*
+ * Re-key protocol routines
+ */
+
+/* Actually takes the new keys into use. */
+
+static void
+silc_client_protocol_rekey_validate(SilcClient client,
+ SilcClientRekeyInternalContext *ctx,
+ SilcSocketConnection sock,
+ SilcSKEKeyMaterial *keymat)
+{
+ SilcClientConnection conn = (SilcClientConnection)sock->user_data;
+
+ if (ctx->responder == TRUE) {
+ silc_cipher_set_key(conn->send_key, keymat->receive_enc_key,
+ keymat->enc_key_len);
+ silc_cipher_set_iv(conn->send_key, keymat->receive_iv);
+ silc_cipher_set_key(conn->receive_key, keymat->send_enc_key,
+ keymat->enc_key_len);
+ silc_cipher_set_iv(conn->receive_key, keymat->send_iv);
+ } else {
+ silc_cipher_set_key(conn->send_key, keymat->send_enc_key,
+ keymat->enc_key_len);
+ silc_cipher_set_iv(conn->send_key, keymat->send_iv);
+ silc_cipher_set_key(conn->receive_key, keymat->receive_enc_key,
+ keymat->enc_key_len);
+ silc_cipher_set_iv(conn->receive_key, keymat->receive_iv);
+ }
+
+ silc_hmac_set_key(conn->hmac, keymat->hmac_key, keymat->hmac_key_len);
+
+ /* Save the current sending encryption key */
+ memset(conn->rekey->send_enc_key, 0, conn->rekey->enc_key_len);
+ silc_free(conn->rekey->send_enc_key);
+ conn->rekey->send_enc_key =
+ silc_calloc(keymat->enc_key_len / 8,
+ sizeof(*conn->rekey->send_enc_key));
+ memcpy(conn->rekey->send_enc_key, keymat->send_enc_key,
+ keymat->enc_key_len / 8);
+ conn->rekey->enc_key_len = keymat->enc_key_len / 8;
+}
+
+/* This function actually re-generates (when not using PFS) the keys and
+ takes them into use. */
+
+void silc_client_protocol_rekey_generate(SilcClient client,
+ SilcClientRekeyInternalContext *ctx)
+{
+ SilcClientConnection conn = (SilcClientConnection)ctx->sock->user_data;
+ SilcSKEKeyMaterial *keymat;
+ uint32 key_len = silc_cipher_get_key_len(conn->send_key);
+ uint32 hash_len = conn->hash->hash->hash_len;
+
+ SILC_LOG_DEBUG(("Generating new session keys (no PFS)"));
+
+ /* Generate the new key */
+ keymat = silc_calloc(1, sizeof(*keymat));
+ silc_ske_process_key_material_data(conn->rekey->send_enc_key,
+ conn->rekey->enc_key_len,
+ 16, key_len, hash_len,
+ conn->hash, keymat);
+
+ /* Set the keys into use */
+ silc_client_protocol_rekey_validate(client, ctx, ctx->sock, keymat);
+
+ silc_ske_free_key_material(keymat);
+}
+
+/* This function actually re-generates (with PFS) the keys and
+ takes them into use. */
+
+void
+silc_client_protocol_rekey_generate_pfs(SilcClient client,
+ SilcClientRekeyInternalContext *ctx)
+{
+ SilcClientConnection conn = (SilcClientConnection)ctx->sock->user_data;
+ SilcSKEKeyMaterial *keymat;
+ uint32 key_len = silc_cipher_get_key_len(conn->send_key);
+ uint32 hash_len = conn->hash->hash->hash_len;
+ unsigned char *tmpbuf;
+ uint32 klen;
+
+ SILC_LOG_DEBUG(("Generating new session keys (with PFS)"));
+
+ /* Encode KEY to binary data */
+ tmpbuf = silc_mp_mp2bin(ctx->ske->KEY, 0, &klen);
+
+ /* Generate the new key */
+ keymat = silc_calloc(1, sizeof(*keymat));
+ silc_ske_process_key_material_data(tmpbuf, klen, 16, key_len, hash_len,
+ conn->hash, keymat);
+
+ /* Set the keys into use */
+ silc_client_protocol_rekey_validate(client, ctx, ctx->sock, keymat);
+
+ memset(tmpbuf, 0, klen);
+ silc_free(tmpbuf);
+ silc_ske_free_key_material(keymat);
+}
+
+/* Packet sending callback. This function is provided as packet sending
+ routine to the Key Exchange functions. */
+
+static void
+silc_client_protocol_rekey_send_packet(SilcSKE ske,
+ SilcBuffer packet,
+ SilcPacketType type,
+ void *context)
+{
+ SilcProtocol protocol = (SilcProtocol)context;
+ SilcClientRekeyInternalContext *ctx =
+ (SilcClientRekeyInternalContext *)protocol->context;
+ SilcClient client = (SilcClient)ctx->client;
+
+ /* Send the packet immediately */
+ silc_client_packet_send(client, ctx->sock, type, NULL, 0, NULL, NULL,
+ packet->data, packet->len, TRUE);
+}
+
+/* Performs re-key as defined in the SILC protocol specification. */
+
+SILC_TASK_CALLBACK(silc_client_protocol_rekey)
+{
+ SilcProtocol protocol = (SilcProtocol)context;
+ SilcClientRekeyInternalContext *ctx =
+ (SilcClientRekeyInternalContext *)protocol->context;
+ SilcClient client = (SilcClient)ctx->client;
+ SilcClientConnection conn = (SilcClientConnection)ctx->sock->user_data;
+ SilcSKEStatus status;
+
+ SILC_LOG_DEBUG(("Start"));
+
+ if (protocol->state == SILC_PROTOCOL_STATE_UNKNOWN)
+ protocol->state = SILC_PROTOCOL_STATE_START;
+
+ SILC_LOG_DEBUG(("State=%d", protocol->state));
+
+ switch(protocol->state) {
+ case SILC_PROTOCOL_STATE_START:
+ {
+ /*
+ * Start protocol.
+ */
+
+ if (ctx->responder == TRUE) {
+ /*
+ * We are receiving party
+ */
+
+ if (ctx->pfs == TRUE) {
+ /*
+ * Use Perfect Forward Secrecy, ie. negotiate the key material
+ * using the SKE protocol.
+ */
+
+ if (ctx->packet->type != SILC_PACKET_KEY_EXCHANGE_1) {
+ /* Error in protocol */
+ protocol->state = SILC_PROTOCOL_STATE_ERROR;
+ protocol->execute(client->timeout_queue, 0, protocol, fd,
+ 0, 300000);
+ }
+
+ ctx->ske = silc_ske_alloc();
+ ctx->ske->rng = client->rng;
+ ctx->ske->prop = silc_calloc(1, sizeof(*ctx->ske->prop));
+ silc_ske_get_group_by_number(conn->rekey->ske_group,
+ &ctx->ske->prop->group);
+
+ status = silc_ske_responder_phase_2(ctx->ske, ctx->packet->buffer,
+ NULL, NULL, NULL, NULL);
+ if (status != SILC_SKE_STATUS_OK) {
+ SILC_LOG_WARNING(("Error (type %d) during Re-key (PFS)",
+ status));
+
+ protocol->state = SILC_PROTOCOL_STATE_ERROR;
+ protocol->execute(client->timeout_queue, 0,
+ protocol, fd, 0, 300000);
+ return;
+ }
+
+ /* Advance the protocol state */
+ protocol->state++;
+ protocol->execute(client->timeout_queue, 0, protocol, fd, 0, 0);
+ } else {
+ /*
+ * Do normal and simple re-key.
+ */
+
+ /* Send the REKEY_DONE to indicate we will take new keys into use */
+ silc_client_packet_send(client, ctx->sock,
+ SILC_PACKET_REKEY_DONE,
+ NULL, 0, NULL, NULL, NULL, 0, TRUE);
+
+ /* The protocol ends in next stage. */
+ protocol->state = SILC_PROTOCOL_STATE_END;
+ }
+
+ } else {
+ /*
+ * We are the initiator of this protocol
+ */
+
+ /* Start the re-key by sending the REKEY packet */
+ silc_client_packet_send(client, ctx->sock, SILC_PACKET_REKEY,
+ NULL, 0, NULL, NULL, NULL, 0, TRUE);
+
+ if (ctx->pfs == TRUE) {
+ /*
+ * Use Perfect Forward Secrecy, ie. negotiate the key material
+ * using the SKE protocol.
+ */
+ ctx->ske = silc_ske_alloc();
+ ctx->ske->rng = client->rng;
+ ctx->ske->prop = silc_calloc(1, sizeof(*ctx->ske->prop));
+ silc_ske_get_group_by_number(conn->rekey->ske_group,
+ &ctx->ske->prop->group);
+
+ status =
+ silc_ske_initiator_phase_2(ctx->ske, NULL, NULL,
+ silc_client_protocol_rekey_send_packet,
+ context);
+
+ if (status != SILC_SKE_STATUS_OK) {
+ SILC_LOG_WARNING(("Error (type %d) during Re-key (PFS)",
+ status));
+
+ protocol->state = SILC_PROTOCOL_STATE_ERROR;
+ protocol->execute(client->timeout_queue, 0,
+ protocol, fd, 0, 300000);
+ return;
+ }
+
+ /* Advance the protocol state */
+ protocol->state++;
+ } else {
+ /*
+ * Do normal and simple re-key.
+ */
+
+ /* The protocol ends in next stage. We have sent the REKEY packet
+ and now we just wait that the responder send REKEY_DONE and
+ the we'll generate the new key, simple. */
+ protocol->state = SILC_PROTOCOL_STATE_END;
+ }
+ }
+ }
+ break;
+
+ case 2:
+ /*
+ * Second state, used only when oding re-key with PFS.
+ */
+ if (ctx->responder == TRUE) {
+ if (ctx->pfs == TRUE) {
+ /*
+ * Send our KE packe to the initiator now that we've processed
+ * the initiator's KE packet.
+ */
+ status =
+ silc_ske_responder_finish(ctx->ske, NULL, NULL,
+ SILC_SKE_PK_TYPE_SILC,
+ silc_client_protocol_rekey_send_packet,
+ context);
+
+ if (status != SILC_SKE_STATUS_OK) {
+ SILC_LOG_WARNING(("Error (type %d) during Re-key (PFS)",
+ status));
+
+ protocol->state = SILC_PROTOCOL_STATE_ERROR;
+ protocol->execute(client->timeout_queue, 0,
+ protocol, fd, 0, 300000);
+ return;
+ }
+ }
+
+ } else {
+ if (ctx->pfs == TRUE) {
+ /*
+ * The packet type must be KE packet
+ */
+ if (ctx->packet->type != SILC_PACKET_KEY_EXCHANGE_2) {
+ /* Error in protocol */
+ protocol->state = SILC_PROTOCOL_STATE_ERROR;
+ protocol->execute(client->timeout_queue, 0, protocol, fd, 0, 300000);
+ }
+
+ status = silc_ske_initiator_finish(ctx->ske, ctx->packet->buffer,
+ NULL, NULL, NULL, NULL);
+ if (status != SILC_SKE_STATUS_OK) {
+ SILC_LOG_WARNING(("Error (type %d) during Re-key (PFS)",
+ status));
+
+ protocol->state = SILC_PROTOCOL_STATE_ERROR;
+ protocol->execute(client->timeout_queue, 0,
+ protocol, fd, 0, 300000);
+ return;
+ }
+ }
+ }
+
+ /* Send the REKEY_DONE to indicate we will take new keys into use
+ now. */
+ silc_client_packet_send(client, ctx->sock, SILC_PACKET_REKEY_DONE,
+ NULL, 0, NULL, NULL, NULL, 0, TRUE);
+
+ /* The protocol ends in next stage. */
+ protocol->state = SILC_PROTOCOL_STATE_END;
+ break;
+
+ case SILC_PROTOCOL_STATE_END:
+ /*
+ * End protocol
+ */
+
+ if (ctx->packet->type != SILC_PACKET_REKEY_DONE) {
+ /* Error in protocol */
+ protocol->state = SILC_PROTOCOL_STATE_ERROR;
+ protocol->execute(client->timeout_queue, 0, protocol, fd, 0, 0);
+ }
+
+ if (ctx->responder == FALSE) {
+ if (ctx->pfs == FALSE) {
+ /* Send the REKEY_DONE to indicate we will take new keys into use
+ now. */
+ silc_client_packet_send(client, ctx->sock,
+ SILC_PACKET_REKEY_DONE,
+ NULL, 0, NULL, NULL, NULL, 0, TRUE);
+ }
+ }
+
+ /* Protocol has ended, call the final callback */
+ if (protocol->final_callback)
+ protocol->execute_final(client->timeout_queue, 0, protocol, fd);
+ else
+ silc_protocol_free(protocol);
+ break;
+
+ case SILC_PROTOCOL_STATE_ERROR:
+ /*
+ * Error occured
+ */
+
+ if (ctx->pfs == TRUE) {
+ /* Send abort notification */
+ silc_ske_abort(ctx->ske, ctx->ske->status,
+ silc_client_protocol_ke_send_packet,
+ context);
+ }
+
+ /* On error the final callback is always called. */
+ if (protocol->final_callback)
+ protocol->execute_final(client->timeout_queue, 0, protocol, fd);
+ else
+ silc_protocol_free(protocol);
+ break;
+
+ case SILC_PROTOCOL_STATE_FAILURE:
+ /*
+ * We have received failure from remote
+ */
+
+ /* On error the final callback is always called. */
+ if (protocol->final_callback)
+ protocol->execute_final(client->timeout_queue, 0, protocol, fd);
+ else
+ silc_protocol_free(protocol);
+ break;
+
+ case SILC_PROTOCOL_STATE_UNKNOWN:
+ break;
+ }
+
+}
+
/* Registers protocols used in client */
void silc_client_protocols_register(void)
silc_client_protocol_connection_auth);
silc_protocol_register(SILC_PROTOCOL_CLIENT_KEY_EXCHANGE,
silc_client_protocol_key_exchange);
+ silc_protocol_register(SILC_PROTOCOL_CLIENT_REKEY,
+ silc_client_protocol_rekey);
}
/* Unregisters protocols */
silc_client_protocol_connection_auth);
silc_protocol_unregister(SILC_PROTOCOL_CLIENT_KEY_EXCHANGE,
silc_client_protocol_key_exchange);
+ silc_protocol_unregister(SILC_PROTOCOL_CLIENT_REKEY,
+ silc_client_protocol_rekey);
}
projects / silc.git / blobdiff